A THUG who left a killer with a serious brain injury was warned that he faces a lengthy prison term for the vicious assault.

Ryan Lafferty claimed his victim – the so-called "wheelbarrow killer" John Foxton, who was jailed in 2007 for one of Scotland's most notorious culpable homicide cases – had been making threats while boasting he had killed somebody before.

A court heard the incident, which happened at around midnight on June 30 was captured on CCTV in Tillicoultry.

Foxton, said to have been "swaying" back towards his home in Sauchie, met Lafferty, 28, near the town centre.

Prosecutor Collette Fallon told Falkirk Sheriff Court that Foxton, 46, "was not able to walk in a straight line".

The depute fiscal said: "The accused then points off camera and beckons Foxton to come with him, and they both walk off together in the direction of Park Street."

Down the street, however, Lafferty was seen on CCTV to punch Foxton once to the face.

Miss Fallon said Foxton fell "straight back", and to the ground.

Friends who had been with Lafferty ran towards the scene and found Foxton "on the floor, unconscious, snoring and bleeding".

The depute fiscal said Lafferty told a friend at the scene that "he and Foxton had been arguing about the speed of their vehicles, which made the accused feel threatened as Foxton made threats and said he would 'do him in' if his car was not faster".

Witnesses called an ambulance, and arrived to find Lafferty – naked from the waist up – cradling Foxton's head while he lay unconscious, unresponsive and bleeding from the left eye.

He was taken to hospital, where he was found to have bleeding and bruising on the brain and a fractured skull and spent more than three months in hospital, two of which were in intensive care.

It was thought he would require long-erm care in an institution, but he eventually recovered enough to be discharged home although he needs "significant support in the community".

Father-of-two Lafferty, of Tillicoultry, admitted a charge of assault to severe injury and impairment. He had initially been charged with attempted murder.

Defence solicitor Virgil Crawford said Lafferty suffered from post-traumatic stress disorder.

He said: "Mr Foxton had been making threats to strike him, pointing out that he had killed somebody before.

"Mr Foxton does have a previous conviction for culpable homicide."

Sentencing on the matter was deferred until January 9, for confirmation of Lafferty's PTSD diagnosis, with the accused remanded in custody in the meantime.

Sheriff Christopher Shead said: "There was some discussion about cars. That's about as far away from provocation as can be.

"If he has been diagnosed with PTSD that's a factor that has to be weighed in the balance, because it's sometimes said people with PTSD can act impulsively and potentially aggressively.

"However, his record is exclusively for crimes of violence – it is likely to be a custodial sentence of some substance."

In 2006, Foxton kicked and battered 19-year-old Ryan Copeland to death after a row in Alloa, then carted his body in a wheelbarrow to the house where Ryan lived with his parents and tipped him out near the doorstep.

He was given a six-and-a-half prison sentence.